"Without a doubt, the rule system that white people love the most is grammar." That's pretty much the only rule system this maverick white boy likes. As you read the article, it seems that the author has taken a mocking tone, as if obsession with grammar rules was somehow strange. Does not everyone experience a knife-in-the-gut feeling when someone says "He gave it to Timmy and I." That gives I major indigestion! And, yes, "if (I) were to catch a mistake in The New Yorker, it would be a sufficient reason for a large party."
But grammar hawking can save your life.